Railway-traffic-controlling apparatus



RAILWAY TRAFFIC CONTROLLING APPARATUS Filed May 16, 1928 A R i 2:?-

INVENTOR Z M .61. W Q- 5. -28

N ATTORNEY Patented Mar. 31, 1925.

UNITED ';S T A TEES "P ATE NT 'FIiTCE EERBElEt-"i A. WALLACE, OF EDG'EWOOD BOROUGH, IPENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF' SWISSVALE, PENNSYLVANIA, A CORPO- RATIO'N OF PENNSYLVANIA.

RAILWAY-TRAFFIC CONTEOLLIN G APPARATUS.

Application filed May 16,

To all whom it may concern:

Be it known that I, HERBERT AWVALLACE, a citizen of the'United States, residing at Edgewood Borough, inthe county of Allegheny and State of'Iennsylvania, have invented certain new and useful Improvements in RailwayTraffic-Controlling Apparatus, of which the following is a speciiication.

My invention relates to railway trafiic controlling apparatus, and particularly to apparatus of the type comprising train carried governing means controlled in part by energy received from the trackway. More particularly my invention relatesto the trackway portion of such apparatus.

I will describe two forms of railway tratiic controlling apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1

is a diagrammatic view showing one form of railway tratiic controlling apparatus embodying my invention. Fig. 2 is a view showing a modification of the apparatus shown in Fig. 1 and also embodying my invention.

Similar reference characters refer to similar parts in-each ot the views.

Referring first to Fig. 1, the reference character 1 designates the track'rails of a railw y over which trafiic normally moves in the direction indicated'bythe 'arrow. These track rails are divided by means of insulating joints 2 into a plurality of insulated track sections of which only one section AB is shown in the drawing. As here shown each of said track sections constitutes a block.

comprises as shown in the drawing, a see- I ondary winding9 of a track transformer T connected across the rails adjacent the exit end of the section. The primary winding 10 of this track transformer T is constantly supplied with alternating current through wires'25 and-26 from line wires6 ted by an alternator G. Interposedbetween secondary-9 of each track transformer and one rail of the associatedsection is an impedance 9* one function of which is to limit the output of the track transformer when its terminals are short-circuited by i the wheels and axles of a train. Section A-B This section is provided with a source of track circult currentwhlch 1923. Serial No. 639,315.

is also provided with a track relay R wh1ch is connected across thezrailsaadjacent the entranceend of the section. It is therefore clear that track section A-'B "is procurrent which I will :hereinatter term .a

local current. As here showmthis current .is supplied to' the two. track Tails 4 in parallel. The immediate source ot'this current is secondary'winding 7 ota local-transformer D whose primary winding'8 is constantly supplied with alternating current from line wires 6. 'An impedance 3 is connected'across the ralls'ad acentthe entrance end of the sect1on,'a similar impedance 5 is connected. across the rails adjacent the exit end'oit the section, and'a third similar impedance at is connected across the rails at some intermediate'point 1n the-section. The

supply of local current to the rails'o'fn the :sect1on IS'COIltIOllQCl' by tratlic conditions in adyance of the section,and as here shown it is controlled by trackrrelay'ld for the section in advance of section.'AB. One

local circuit passes from the right hand terminal of. secondary winding? of local transformer D,'through'w1res 19 and 21,

front contact 11-14: of relay R wire 22, to the mid point of impedance 5, thence through the rails of section A B to imipedance 3, wire 24:,t'ront contact 13 16 of :relay R and wire 18'baclr'to the left han'd terminal of secondary winding 7 This circult is closed only when relay R is'enei gized, under WlllCll 'conditlon current *of 'what I will term normal relative polarity is supplied to the'rails of section -A B from end to end. Another-circuit is provided which'passes from the right'hand-ter- 1 minal of secondary 7 through wires '19 and 20, back contact 1317 of relay R wire 24, to the mid-point of impedance 3, thence through the rails in parallel of section AB to impedance l, thence through wire 23, back contact 1215 ofrelay R and I wire 18, back to the lefthand terminal of secondarywinding '1'. This circuit is closed only when relay R is deenergized, under which conditions current of :what I shall term reverse relative polarity is supplied to the rails of section AB between impedances 3 and 4.

It will thus be seen that the relay contacts 11, 12, and 13, constitute a pole changer for supplying local current of one relative polarity from secondary 7 tothe rails of section AB throughout the entire length of the section, or local current of the other relative polarity from the same secondary 7 to the rails of section AB from the entrance end 3 to the intermediate point 4 in the section.

It is understood that while only one of the track sections of the railway is shown in the drawing a plurality of successive sections will ordinarily be equipped with apparalgus similar to that shown for section A Before explaining the operation of the apparatus it should be pointed out that the .trackway apparatus here shown is intended for cooperation with train carried governing apparatus which operates in the following manner: When the train occupies a section of track which is supplied with track circuit current and also with local current of normal relative polarity the governing apparatus gives a proceed indication. When the train is on a portion of track which is supplied with track circuit current and with local current of reverse relative polarity the governing apparatus gives a caution indication. WVhen the train is on a portion of track from which the supply of either local current or track circuit current is interrupted, the governing apparatus gives a stop, or slow, indication.

As shown in the drawing, the parts are in normal position, that is, the positions corresponding to an unoccupied condition of section AB and the next section in advance. I will now assume that a train traveling in the direction of the arrow enters section AB. The train will receive a proceed indication through section AB since it is supplied with track circuit current and local current of normal relative polarity. As this train enters the track section to the right of point B, track relay R will become de-energized, thus reversing the local current between impedances 3 and 4, and dis continuing the local current between impedances 4 and 5 in section AB. While such train occupies the section to the right of point B, a following train entering section A-B will accordingly receive a caution indication between impedances 3 and 4, and a stop or slow indication between impedances 4 and 5.

In Fig. 2 each section is provided with a signal designated by the reference character S with an exponent corresponding to the location, each of which signals is, as here shown, of the three-position semaphore type adapted to indicate proceed, caution or stop Each signal is controlled, by means not shown in the drawing but including the associated track relay, in such a manner that when the corresponding section is occupied the signal indicates stop when the corresponding section is unoccupied and the section next in advance is occupied, the signal indicates caution, and when the corresponding section and the section next in advance are both unoccupied, the signal indicates proceed. In this view all the rest of the apparatus is the same as that shown in Fig. 1 except that the local circuits for section A-B are controlled by means of a circuit controller P operated by signal S for the section in advance of B. When signal S is at proceed or caution the circuit controller P occupies the position shown in the drawing and local current then flows from secondary 7 of transformer D, through wire 19, circuit controller P wire 22, impedance 5 in section AB, through the rails of the section in parallel to impedance 3, wire 24, circuit controller P and wire 18 back to secondary 7 of transformer D, under which conditions section A'B is supplied with local current ofnormal relative polarity throughout the length of the section. If, however, signal S is at stop, circuit con troller P is reversed, and local current then flows from secondary 7 of local transformer 1),, through wire 19, circuit controller P wire 24, impedance 3 in section A-B, through the rails of the section in parallel to impedance 4, wire 23, circuit controller P and wire 18, back to secondary 7 of transformer D. When this circuit is closed section A'B is supplied with local current of reverse relative polarity between impedances 3 and 4 but with no local current between impedances 4 and 5.

It will thus be seen that the circuit controller P constitutes a pole changer for supplying local current of one relative polarity from secondary 7 to the rails of the section AB throughout the entire length of the section or local current of the other ralative polarity from the same secondary 7 to the rails of section A-B between impedances 3 and 4.

A train passing through the stretch of track shown in the drawing operates the apparatus exactly as described in connection with Fig. 1 and the functioning of the apparatus will be clear without further explanation.

One feature of my invention is the provision of means for supplying local current to each section from a single source of energy located at one end of the section and controlled by a simple arrangement of contacts responsive to traffic conditions in advance of the section.

Although I have herein shown and described only two forms of railway traffic controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention what I claim is:

1. In combination, a section of railway track, an impedance connected across the rails adjacent one end of said section, a second impedance connected across the rails ad jacent the other end of said section, a third impedance connected across the rails at an intermediate point in said section, a source of energy, a normally closed contact for connecting said first impedance with one terminal of said source, a normally closed contact for connecting said second impedance with the second terminal of said source, a normally open contact for connecting said second impedance with the said first terminal, a normally open contact for connecting said third impedance with the said second terminal, and a track relay connected with the rails of the section next in advance and including said contacts.

2. In combination, a first and a second section of railway track, a track relay for said first section, and means controlled solely by said relay for supplying said second section with local current of one relative polarity throughout the length of the section, or with local current of the other relative polarity through a portion only of the section from a single energy source.

3. In combination, a section of railway track, a source of local train governing current for said section, and a single pole changer controlled by traflic conditions in advance of said section for supplying local current of one relative polarity from said source to the rails of the section throughout the length of the section or for supplying local current of the other relative polarity from said source to the rails of the section through a portion of the section.

4:. In combination, a section of railway track, a source of local train governing current for said section, and a single pole changer controlled by traffic conditions in advance of said section for supplying local current of one relative polarity from said source to the rails of the section throughout the length of the section or for supplying local current of the other relative polarity from said source to the rails of the section from the entrance end of the section to an intermediate point in the section.

5. In combination, a section of railway track, an impedance connected across the rails adjacent one end of said section, a second impedance connected across the rails ad; jacent the other end of said section, a third impedance connected across the rails at an intermediate point in said section, a source of energy, a normally closed contact for connecting said first impedance with one terminal of said source, a normally closed contact for connecting said second impedance with the second terminal of said source, a normally open contact for connecting said second impedance with the said first terminal, a normally open contact for connecting said third impedance with the said second terminal, and a signal for the section next in advance for controlling said contacts.

In testimony whereof I afiix my signature.

HERBERT A. WALLACE. 

